This relates generally to electronic devices and, more particularly, to power protection circuitry for electronic devices.
Electronic devices such as cellular telephones, media players, tablet computers, and other devices are often coupled to accessories. For example, an accessory device may have a display, speakers, or other components that can be used by a host electronic device in playing media files or other content for a user.
During normal operation, the host device may supply power to the accessory. If the accessory is defective or poorly designed, the accessory may supply power to the host device rather than drawing power from the host device. This behavior, which may sometimes be referred to as back-powering, may cause damage to the host device.
It would therefore be desirable to be able to provide protection circuitry for preventing damage from back-powering when accessories are coupled to the electronic device.